The long-range purpose is to provide an understanding of the use of the basic acoustic patterns in speech perception by hearing-impaired persons. Particularly, information is sought that would form a basis for designing eventual speech-processing systems and adjusting these systems for the individual. The use of major acoustic cues to consonant perception by the hearing-impaired, and speech-cue enhancement are studied using consonant stimuli from naturally spoken syllables, chosen on the basis of frequency of occurrence in conversations. The consonants studied will be fricatives and stops in intervocalic, initial, and final positions. and /n,1/ in intervocalic position. The cues studied are those that distinguish stop/fricative, voiced/voiceless, place of articulation, nasal, and lateral. Enhancements, studied for fricatives and stops, are friction/burst amplification, murmur amplification, and spectral exaggeration. Discrimination training paradigms for individual listeners' use of cue-enhancements are also studied.